* Add nph check to fluffy CI lint
* Add a section on nph usage in the fluffy.guide
* Update copyright years for altered files
* Avoid chained methods formatting style in db code
* Update nph in CI to v0.5
* Remove leftover commented import
* Move comment to avoid nph turning complex list into simple list (nph bug)
* Update nph in CI to v0.5.1
* Formatting fluffy with nph v0.5.1
* Reduce Nim 1.6 compiler warnings/hints for Fluffy and Nimbus proxy
Mostly raises Defect removals, TaintedString removal and some
unnecessary imports.
Also updating the copyright years alongside.
* Further reduce Nim 1.6 compiler warnings/hints for Nimbus
* Move BlockHeaderWithProof content to content key selector 0
- Remove as content type with content key selector 4
- Replace regular block header with BlockHeaderWithProof at
content key selector 0
* Apply blockHeader content key also to bridge
* Add tests for header with proof generation and verification